Katherine Heigl had experience adopting internationally after welcoming a first daughter, Naleigh, now 4, from South Korea.

But when she and her husband Josh Kelly were ready to add "Miss Adelaide" to the family four months ago, they chose domestic adoption.

"This was fascinating because we started the adoption process again and we thought we were gonna adopt internationally," Heigl said last night on The Tonight Show with Jay Leno, reported Access Hollywood. "It's a pretty long process. It can take years."

"And then we started exploring because we had heard that Korea had gotten very hard to adopt from, and China had a very, very long waiting list and I was like, any day now," she continued. "And so we started exploring the idea of domestic adoption – just exploring – and then my lawyer called and said, 'There's a birth mother and she's due in four weeks and she's all yours if you want her.'"

Heigl shared a picture of she and Kelly sweetly kissing Adelaide's cheeks on the show, and told Leno it was a surprise to her husband that the addition to their family came so swiftly.

"I had to talk Josh into that one," she said, laughing. "He thought it was gonna be a few years, and that we were gonna end up with more of like a 9-month-old or 10-month-old, and he looked at me and said, 'You're telling me in a month we're gonna have a newborn?' And I said, 'Yes. It's perfect timing, don't you think? Look we're bothhere, we're not working. This is great. We can spend time with her.' And it has been beautifully serendipitous and graceful, because we've gotten to spend all this wonderful time with her."